Publications WO 2008/056275 A1 and WO 2007/045937 A1 disclose that when pairing mobile devices using the Bluetooth standard request an addressed terminal device to emit an optical signal pattern, they conduct the pairing with the identified terminal device only when this signal pattern is detected by the initiating mobile device.
Wireless terminal devices or OBUs are often produced without being assigned to a specific user or area of use and are only initialised with the specific data upon issue and transferred to the user. In this case, the initialisation generally occurs directly in the location where the terminal device is issued or sold, the so-called point of sale (POS), by means of a special programming station, which inputs the initialisation or personalisation data into the terminal device via the radio interface (radio programming).
Even if the radio interface between the programming station and the terminal device has a constantly restricted range, for example, if WLAN (wireless local area network), WAVE (wireless access in a vehicle environment) or DSRC (dedicated short-range communication) interfaces are used, or even occurs in a screened interior of the programming station, it still may be the case that a stack of “fresh” terminal devices lies too closely to the programming station at the POS and that besides the terminal device to be programmed. Further terminal devices are thus unintentionally programmed along with it, with the risk that the user is provided with a device that has not been programmed or an incorrectly programmed terminal device comes into circulation.